1. Field of the Invention
This invention pertains to an electronic device characterized by a semiconductor film disposed on a growth surface of a sapphire substrate wherein the growth surface is off a-axis.
2. Description of the Related Art
The growth of high quality semiconducting films of III/V elements of the Periodic Table on a sapphire substrate has been a topic of major interest in recent years. Attempts have been made to improve the material quality of the films by optimizing essential growth parameters such as temperature, buffer layer, and the chemical composition of the film constituents. However, the role of the vicinal angle, while recognized in some materials such as gallium arsenide on silicon, has remained unexplored in the case of the semiconducting films on sapphire substrates. It is known that growth of a film on basal plane (0001) or the c-plane of sapphire substrates through off c-plane angles of up to 10.degree. have shown to be of little help in improving the overall quality of the film.